1. Field of the Invention
The present invention relates to unmanned, autonomous, waterborne vehicles for marine use, herein referred to as unmanned ocean vehicles (UOVs). In particular, although not exclusively, the invention relates to unmanned ocean vehicles utilising renewable energy sources which enable extended periods of operation, such as in remote ocean surface surveillance.
2. Discussion of the Background Art
The military, governmental and commercial uses for UOVs in warfare, exploration, research and monitoring applications at sea are numerous. The ability of conventional platforms, such as ships and buoys, to gather data and information in these applications is limited, particularly when compared to the vastness of the world's oceans. Ships are expensive to build, man, and operate. Buoys, either fixed or floating, generally provide only pinpoint coverage. Whilst some additional data may now be gathered remotely by satellites, they are more expensive and their sensors can provide very limited ocean data.
The sensors and instruments available to gather oceanographic data and information directly are well developed. It is clear that modern communications and information technology may be used to fully exploit extended networks of instruments and sensors, such as described in U.S. Pat. No. 5,894,450 to Schmidt et al. However, a desirable element is an inexpensive, mobile, and self-sustaining platform that could provide power and connectivity for ocean surveillance, communications, research and other applications requiring endurance.
Conventional unmanned surface vehicles, such as described in U.S. Pat. No. 5,713,293 to Shiffler et al. or the Spartan “scout” vehicle proposed by the US Naval Undersea Warfare Centre of Newport, R.I., USA, typically employ conventional fossil fuelled power units that provide limited range and endurance. Conventional unmanned surface vehicles, at least when operating in a semi-autonomous mode, are also subject to the threat posed by collision or close encounters with larger vessels.